Saccharomyces yeasts are model organisms, and may be useful as indicators of climate change. In North America, S. cerevisiae, the model laboratory organism, also grows wild in subtropical and warm temperate forests. Its sister species, S. paradoxus, grows wild in cooler temperate forests. I am working at a Primarily Undergraduate-Serving Institution, Wheaton College (MA), and leading undergraduate students interested in the impacts of climate change and other anthropogenic environmental changes. We are sampling Saccharomyces from Harvard Forest experimental plots to look for patterns in Saccharomyces species distributions, and in phenotypes associated with warming and nitrogen treatments.